My wife and I have looked in this and even did some of the initial steps. We realized it wasn’t the right time and still plan on it for the future.
We are in California as well. The program we found is free. Just need some basic stuff like first aid, a home visit, background check etc. Look into Fost Adopt “foster adopt”. They are foster kids who have a very low chance of being sent back to their parents and they are trying to find permanent homes.
We felt it was a pretty easy process, it might take a week, or a year, depends on what you are hoping for. You can pick she range, gender, ethnicity, and what level of medical/abuse/ other needs you are willing to facilitate.
There should be plenty of options in the Bay Area like this, you shouldn’t need to spend more then $300 to go this route. The child will also come with their own medical insurance and living stipend. I forget how much $$ it was, went up as they got older. Maybe like 700 for little kids. Our plan was to put it into some type of trust for them.
If your connected to a church, or know someone who is, ask them to contact their pastor and let them know what you are trying to do, there is probably a 100% chance someone attending has adopted and would be willing to give you some advice on options.
Good luck in your journey.